Re: how do i know if its a 428
429 or 428? 429 is a 385 series. 428-390 a FE series. FE has 5 valve cover bolts and the heads and intake join together under the valve cover. 66-70 production 428's never came in trucks. So it's a transplant if a 428. 390's yes they came in the F150s. You'll have to do a little detective work. FE's are pretty generic looking on the outside. And most of the casting numbers are too. 428 blocks from 66-70 were marked with a A,C or S sandscratch on the back of the block. Later 428 blocks were service replacements which had no markings or casting number just foundry ID and date code. Best to measure the cyl bore and stroke to be positive of what you have. Especially if you want to sell.
428- 4.13 bore std, 3.98 stroke.
390- 4.05 bore std, 3.78 stroke.
Good 390 cores are $200-400 depending where you are. 428 cores really depend on the timeframe and parts on the engine. CJ, PI or std. Value can range from $800 to a few thousand...maybe more depending.
So tell me what you see on the back of the block if anything. And what number you see on the front left of the block, 352 or a reverse 105. Also the head casting number between the center 2 spark plugs. If you have easy access to the crank get the number off #7 counterweight edge. At worst you have to remove a head to get the true bore if we can't figure it out.